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Re: Range, food for thought

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Everytime I see a YT video or even post in the forums about long range, it pretty much always concentrates on the transmission power of the RC and if wanting to extend the range there is also only talk about boosted antennas for the RC, however only once have I read or seen/heard anything about the transmission power of the AC antennas. Correct me if I'm wrong, but since the video signal is being transmitted from the AC, shouldn't the transmission signal from the AC be the one boosted to increase range? Flight controls seem to not require the banwith or strength that the video signal needs. Now, does the RC actually reach out to the AC in order to receive the signal and pull it in? I know, I am ignorant about these things, but I believe the question is valid. The other day I saw a post or ad about someone modding the AC antena and replacing it with a "cloverleaf" one placed hanging down in the back of the inspire, am I wrong in believing that such an antenna will increace the range of transmission from the AC to the RC receiver, therefore increasing the quality and range of video signal?
 
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Everytime I see a YT video or even post in the forums about long range, it pretty much always concentrates on the transmission power of the RC and if wanting to extend the range there is also only talk about boosted antennas for the RC, however only once have I read or seen/heard anything about the transmission power of the AC antennas. Correct me if I'm wrong, but since the video signal is being transmitted from the AC, shouldn't the transmission signal from the AC be the one boosted to increase range? Flight controls seem to not require the banwith or strength that the video signal needs. Now, does the RC actually reach out to the AC in order to receive the signal and pull it in? I know, I am ignorant about these things, but I believe the question is valid. The other day I saw a post or ad about someone modding the AC antena and replacing it with a "cloverleaf" one placed hanging down in the back of the inspire, am I wrong in believing that such an antenna will increace the range of transmission from the AC to the RC receiver, therefore increasing the quality and range of video signal?

The aircraft transmitter's power output is controlled by the receiver. That's why Teradek has a 10000 now that uses your existing 3000 transmitter. Increase the gain on the receiver and you get better range
 
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The aircraft transmitter's power output is controlled by the receiver. That's why Teradek has a 10000 now that uses your existing 3000 transmitter. Increase the gain on the receiver and you get better range
thanks for the insight, I have to wrap my head around the idea that the receiver's power controls the transmission of a remote signal, sorry old and ignorant here.
 
thanks for the insight, I have to wrap my head around the idea that the receiver's power controls the transmission of a remote signal, sorry old and ignorant here.

Right now all HD transmission systems have the receiver doing all the hard work. For instance, when you power up the transmitter it starts scanning all of its channels on order to find the empty ones and the ones farthest from any active channels, then it handshakes with the transmitter Tells it what channel to be on and tells it what power to start at and calculates the range based on time of flight of the signal. The longer it stays on the more it refines the channel and power settings.
 
Right now all HD transmission systems have the receiver doing all the hard work. For instance, when you power up the transmitter it starts scanning all of its channels on order to find the empty ones and the ones farthest from any active channels, then it handshakes with the transmitter Tells it what channel to be on and tells it what power to start at and calculates the range based on time of flight of the signal. The longer it stays on the more it refines the channel and power settings.
Doesn't it make sense then to have a better more efficient antenna at the aircraft so the RC doesn't have to work so hard?
 
My theory is that it’s far easier to enhance and make the stationary RC do all the hard work, than to engineer a light, powerful, battery-conserving, and not too costly transmitter on the A/C.

Doesn't it make sense then to have a better more efficient antenna at the aircraft so the RC doesn't have to work so hard?
 
My theory is that it’s far easier to enhance and make the stationary RC do all the hard work, than to engineer a light, powerful, battery-conserving, and not too costly transmitter on the A/C.

You are correct. The transmitter has to be omnidirectional, lightweight and power efficient. The receiver can jack up its gain with no regard to battery life
 
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Everytime I see a YT video or even post in the forums about long range, it pretty much always concentrates on the transmission power of the RC and if wanting to extend the range there is also only talk about boosted antennas for the RC, however only once have I read or seen/heard anything about the transmission power of the AC antennas. Correct me if I'm wrong, but since the video signal is being transmitted from the AC, shouldn't the transmission signal from the AC be the one boosted to increase range? Flight controls seem to not require the banwith or strength that the video signal needs. Now, does the RC actually reach out to the AC in order to receive the signal and pull it in? I know, I am ignorant about these things, but I believe the question is valid. The other day I saw a post or ad about someone modding the AC antena and replacing it with a "cloverleaf" one placed hanging down in the back of the inspire, am I wrong in believing that such an antenna will increace the range of transmission from the AC to the RC receiver, therefore increasing the quality and range of video signal?

Interesting points. A lot of the "gotta have more range" crowd are never satisfied with the "stock" equipment, proobably because they are flying BLVOS, or in areas with strong EM interference.
 
I am actually not flying blos I’m trying to have a clean signal which where I’m currently flying regularly gets narly around 2500 feet where I can still see the craft, but if incan’t See my subject I makes my composition difficult at best. I need to see focus in addition and if the image is pixelating and blanking our, I can’t do. I have no interest in traveling miles over the city, I fly over the water and try to stay away from people as even if boats are my subject. However I cannot photograph those things I want to on the water by being directly under them.
 
I am actually not flying blos I’m trying to have a clean signal which where I’m currently flying regularly gets narly around 2500 feet where I can still see the craft, but if incan’t See my subject I makes my composition difficult at best. I need to see focus in addition and if the image is pixelating and blanking our, I can’t do. I have no interest in traveling miles over the city, I fly over the water and try to stay away from people as even if boats are my subject. However I cannot photograph those things I want to on the water by being directly under them.

For the UK, BVLOS is considered to be anything beyond 500m or 1,640 ft....
 
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It is not much different here, most local law enforcement has no idea and I think it comes down to whether the officer is into or interested in drones or not. Park rangers for the most part are aware of the Park rules and very likely if they catch you will ask you to land and leave or put the craft away nd enjoy the park without flying, however there was a documented instance of a pilot getting a visit from fish and wildlife in his house the morning after flying in a wildlife conservation area, that allegedly was not posted as such, he was hit with a hefty fine hand delivered, I don't remember the amount but it WAS hefty. However I still try to abide by the rules for the most part and to date am not aware of having broken any.
 
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Would the image transmission benefit from a more efficient antenna even without boosting and/or taxing the battery life, or is the OEM antenna system as efficient as it can be? Would the transmission benefir from a "cloverleaf" antenna? (I think that's what it's called)
 
Perhaps. I'm not an electrical / RF engineer so I will leave the more technical aspect of antenna design to the experts. I just like to point out that a lot of product engineering is about compromises, in terms of performance, cost, price point, and aesthetics. Even if a cloverleaf antenna may improve performance (maybe marginally?), DJI, in my humble opinion, made a good call to not stick a bunch of antennae out of a very beautifully designed aircraft.

Would the image transmission benefit from a more efficient antenna even without boosting and/or taxing the battery life, or is the OEM antenna system as efficient as it can be? Would the transmission benefir from a "cloverleaf" antenna? (I think that's what it's called)
 
Would the image transmission benefit from a more efficient antenna even without boosting and/or taxing the battery life, or is the OEM antenna system as efficient as it can be? Would the transmission benefir from a "cloverleaf" antenna? (I think that's what it's called)
RF transmission will always benefit from a more efficient antenna but upping the gain on a transmitting device means you fall foul of FCC/OFCOM laws for EIRP from a fixed 2.4/5.8ghz device. The best legal way to do it would be to have a far more efficient front end on the receiver coupled with a high gain receiver antenna.

DJI's antennas are nothing more than a wire stub being a crude omni-directional dipole. About as inefficient as you can get!
 
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Would the image transmission benefit from a more efficient antenna even without boosting and/or taxing the battery life, or is the OEM antenna system as efficient as it can be? Would the transmission benefir from a "cloverleaf" antenna? (I think that's what it's called)
Usually higher gain antennas are directional, which is a problem to manage on the AC. Ground stations can easily have trackers, or it’s pretty easy to manually orient your directional antenna towards your AC. But tracking for an AC mounted directional antenna would be very dynamic as the AC changes orientation to the GS often. Tracking on the AC would be heavy and complex.
 
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